[SVXX]

Hello all...this is my first post in these forums and surely won't be the last!

My query is regarding the mechanism/way of functioning of the reagent Cu in Benzene.
I have a substrate, namely diphenyl dichloro methane. When I react it with the reagent in question, I get the product (Ph)₂C=C(Ph)₂.
I have no idea how this occurs. At first I thought of an alpha-elimination catalyzed by copper to form a carbenoid...but I don't seem to understand how it will result in an alkene.
So I'd be grateful if someone could pinpoint the mechanism of the reaction to me.

[g-bones]

carbenoids dimerize to form alkenes.  Think about as if its a singlet carbene (even though it is likely a triplet carbene).  The pair of electrons in the filled orbital of one carbene (A) will enter the empty orbital of another carbene (B).  at the same time the electrons in the filled orbital of B  can enter the empty orbital of carbene A.  overall a double bond is formed.

[SVXX]

Ah many thanks...I looked up carbene dimerization and found http://wikipedia.org/wiki/Persistent_carbene as a result. One such example is in diamino-carbenes : http://en.wikipedia.org/wiki/File:Diaminocarbene_dimer.png. Diphenylcarbene is also a persistent carbene it seems, as it is stable.

[AnkurGel]

@SVXX: That solved the Trouble of The Day